Dspace 8.1 fresh install returns 503

[test test]

Can you please tell me whats wrong with my configuration?
Apache server acts as proxy server.

System details below:

VM: Debian 12.9
IP: 192.168.7.6

/etc/hosts:
192.168.7.6     dspace.ansbb.edu.pl
192.168.7.6     dsadmin.ansbb.edu.pl

Http server: apache2, v. 2.4.62

Apache backend config:
<VirtualHost *:80>
        ServerName dsadmin.ansbb.edu.pl
        Redirect permanent / https://dsadmin.ansbb.edu.pl
</VirtualHost>
<IfModule mod_ssl.c>
        <VirtualHost *:443>
                ServerName dsadmin.ansbb.edu.pl
                ProxyPreserveHost On
                RequestHeader set X-Forwarded-Proto https
                SSLEngine On
                SSLCertificateFile /etc/apache2/ssl/ansbb.edu.pl/2024/certificate.crt
                SSLCertificateKeyFile /etc/apache2/ssl/ansbb.edu.pl/2024/private.key
                SSLCertificateChainFile /etc/apache2/ssl/ansbb.edu.pl/2024/root_ca.ca
                SSLCACertificateFile /etc/apache2/ssl/ansbb.edu.pl/2024/root_ca.ca
                ProxyPass /server http://localhost:8080/server
                ProxyPassReverse /server http://localhost:8080/server
                ErrorLog ${APACHE_LOG_DIR}/dsadmin-prod-https-error.log
                CustomLog ${APACHE_LOG_DIR}/dsadmin-prod-https-access.log combined
                LogLevel alert rewrite:trace3
        </VirtualHost>
</IfModule>

Apache frontend config:
<VirtualHost *:80>
        ServerName dspace.ansbb.edu.pl
        Redirect permanent / https://dspace.ansbb.edu.pl
</VirtualHost>
<IfModule mod_ssl.c>
        <VirtualHost *:443>
                ServerName dspace.ansbb.edu.pl
                ProxyPreserveHost On
                RequestHeader set X-Forwarded-Proto https
                SSLEngine On
                SSLCertificateFile /etc/apache2/ssl/ansbb.edu.pl/2024/certificate.crt
                SSLCertificateKeyFile /etc/apache2/ssl/ansbb.edu.pl/2024/private.key
                SSLCertificateChainFile /etc/apache2/ssl/ansbb.edu.pl/2024/root_ca.ca
                SSLCACertificateFile /etc/apache2/ssl/ansbb.edu.pl/2024/root_ca.ca
                ProxyPass /server ajp://localhost:8009/server
                ProxyPassReverse /server ajp://localhost:8009/server
                ProxyPass / http://localhost:4000/
                ProxyPassReverse / http://localhost:4000/
                ErrorLog ${APACHE_LOG_DIR}/dspace-prod-https-error.log
                CustomLog ${APACHE_LOG_DIR}/dspace-prod-https-access.log combined
                LogLevel alert rewrite:trace3
        </VirtualHost>
</IfModule>

Tomcat server: v. 10.1.34

server.xml:
<Connector port="8080" protocol="HTTP/1.1"
    connectionTimeout="20000"
    redirectPort="8443"
    maxParameterCount="1000"
    minSpareThreads="25"
    enableLookups="false"
    disableUploadTimeout="true"
    URIEncoding="UTF-8"
    />

<Connector protocol="AJP/1.3"
    address="::"
    port="8009"
    redirectPort="8443"
    maxParameterCount="1000"
    URIEncoding="UTF-8"
    />

Dspace frontend and backend: v. 8.1
Solr: v. 8.11.4

Dspace backend local.cfg:
dspace.dir=/opt/dspace
dspace.server.url = https://dsadmin.ansbb.edu.pl/server
dspace.server.ssr.url = ${dspace.server.url}
dspace.ui.url = https://dspace.ansbb.edu.pl
solr.server = http://localhost:8983/solr
db.url = jdbc:postgresql://localhost:5432/dspace
db.username = testing
db.password = testing123

Dspace backend config.prod.yml:
debug: true
ui:
  ssl: true
  host: dspace.ansbb.edu.pl
  port: 4000
  nameSpace: /
  useProxies: true

rest:
  ssl: true
  host: dsadmin.ansbb.edu.pl
  port: 443
  nameSpace: /server
  # ssrBaseUrl: https://dsadmin.ansbb.edu.pl/server

Yarn test:
yarn test:rest
yarn run v1.22.22
$ ts-node --project ./tsconfig.ts-node.json scripts/test-rest.ts
Building production app config
Overriding app config with /root/downloads/dspace_frontend_src/config/config.yml
Overriding app config with /root/downloads/dspace_frontend_src/config/config.prod.yml
...Testing connection to REST API at https://dsadmin.ansbb.edu.pl/server/api...

RESPONSE: 200  

Checking JSON returned for validity...
        "dspaceVersion" = DSpace 8.1
        "dspaceUI" = https://dspace.ansbb.edu.pl
        "dspaceServer" = https://dsadmin.ansbb.edu.pl/server
        "dspaceServer" property matches UI's "rest" config? true
        Does "/api" endpoint have HAL links ("_links" section)? true
Done in 2.59s.

Log errors:
Apache:
192.168.2.143 - - [10/Mar/2025:11:58:31 +0100] "GET / HTTP/1.1" 503 920 "-" "Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/134.0.0.0 Safari/537.36"

[Alan Charly Gastelo Benavides]

dspace.ansbb.edu.pl is pointing to  192.168.7.6 ?
if not, this is the problem, try using 192.168.7.6 in ui:host